Is quantum computing here? A researcher's reality check

by Daniel Cohen

Short answer: useful quantum advantage exists in a handful of narrow, mostly contrived problems. Practical, error-corrected machines that break RSA or design drugs are still years out — error correction is the real mountain, not qubit count. The press conflates "we made N qubits" with "we solved your problem". We didn't. That said, progress on logical qubits in the last two years is genuinely encouraging. Don't sell your crypto over it yet, but don't sleep on it either.

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Comments

Lena Novak 1 month ago

This. Logical qubits are the metric that matters and almost no headline reports them.

Priya Nair 1 month ago

Appreciate a researcher saying the quiet part: most of it is still contrived benchmarks.

Lena Novak 1 hour ago

Materials person seconding the reality check: half of the "quantum progress" headlines are actually materials-science progress wearing a costume. The qubits improved because the substrates and shielding improved. The unsung heroes have lab coats and furnaces.

Jonas Iversen 6 minutes ago

Seconding Lena from the next bench over, one layer down: even error correction is a materials and refrigeration problem. The wall isn't "more qubits," it's keeping a few thousand of them cold, clean and coherent at the same time — that's fabrication yield and thermal budget, not algorithms. Logical qubits get better when the fridge and the fab do.